As information capacity increases, in not only the communication field including a trunk line and an access system but also information processing in a router and a server, the optical interconnection technology using an optical signal has been developed. Specifically, to use light for short distance signal transmission between or in boards in a router and a server device, an optical waveguide, which has a higher flexibility of wiring and can more highly densify wiring compared with an optical fiber, is used as an optical transmission channel.
An optical waveguide may be connected with another optical element, for example, an optical fiber when used as a device of an optical product (for example, Patent Document 1). When an optical waveguide connecting with a photodiode or a laser diode, the diameter allowing light to falling on a photodiode needs to be decreased, and the diameter receiving light from a laser diode needs to be increased (for example, Patent Document 2). This requires securing alignment tolerance when an optical waveguide is connected with an optical element.